Alignment features that allow for a liquid filled layered stack to assemble

ABSTRACT

Apparatus and systems for an ophthalmic device having alignment features that aid assembly of a liquid filled layered stack are disclosed herein. An example apparatus may include first, second, and third optical elements arranged in a stack, with each optical element including alignment and separation features. The alignment and separation features may form an optic region and a dam region. The optic region encircles an optical axis of each of the optical elements. The dam region includes a first dam formed due to the first and second optical elements being in contact, and a second dam formed due to the second and third optical elements being in contact, wherein the dam region determines an optic region gap width.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/278,394, filed on Sep. 28, 2016, the contents of which areincorporated herein by reference.

TECHNICAL FIELD

This disclosure relates generally to ophthalmic devices, and inparticular but not exclusively, relates to alignment and separationfeatures on optical elements of stacked lens structures.

BACKGROUND INFORMATION

Presbyopia may be treated with wearable or implantable lenses thatprovide accommodation. For example, a lens may provide accommodationthrough electrical stimulation of liquid crystal material included inthe lens. The lenses, either implanted or worn on the surface of the eyesimilar to a contact lens, may include multiple layers of material toprovide the accommodation and associated control.

The multiple layers, however, may complicate fabrication of the lens dueto the size of the components that form the multiple layers andalignment requirements. For example, an optical axis of the lens may addan alignment constraint to the fabrication of the lens. Misalignment ofthe optical axis of the multiple layers may result in blurred vision.While many fabrication techniques may be available to provide thedesired alignment, additional factors of the lens may not be addressedby such techniques.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the invention aredescribed with reference to the following figures, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified. Not all instances of an element arenecessarily labeled so as not to clutter the drawings where appropriate.The drawings are not necessarily to scale, emphasis instead being placedupon illustrating the principles being described.

FIG. 1A is a plan view of an ophthalmic device including alignment andseparation features in accordance with an embodiment of the disclosure.

FIG. 1B is a perspective view of an ophthalmic device includingalignment and separation features in accordance with an embodiment ofthe disclosure.

FIG. 2 is a cross-sectional view of an optical stack including alignmentand separation features in accordance with an embodiment of thedisclosure.

FIG. 3 is an illustrative cross-sectional view of a portion of anophthalmic device 300 including alignment and separation features inaccordance with an embodiment of the disclosure.

FIG. 4 is a functional block diagram of an ophthalmic device includingalignment and separation features in accordance with an embodiment ofthe present disclosure

DETAILED DESCRIPTION

Embodiments of a system and apparatus that include alignment andseparation features on optical elements of stacked lens structuresallowing for the assembly of the stacked lens structures are describedherein. In the following description numerous specific details are setforth to provide a thorough understanding of the embodiments. Oneskilled in the relevant art will recognize, however, that the techniquesdescribed herein can be practiced without one or more of the specificdetails, or with other methods, components, materials, etc. In otherinstances, well-known structures, materials, or operations are not shownor described in detail to avoid obscuring certain aspects.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present invention. Thus, theappearances of the phrases “in one embodiment” or “in an embodiment” invarious places throughout this specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments.

FIGS. 1A and 1B are a plan view and a perspective view, respectively, ofan ophthalmic device 100 in accordance with an embodiment of the presentdisclosure. The ophthalmic device 100 may be an on-eye wearable device,such as a contact lens, or an implantable device, such as an intraocularlens (IOL). In some embodiments, the ophthalmic device 100 may beimplemented as a smart contact lens that mounts over a user's eye or asan IOL that is implanted into the anterior chamber, the posteriorchamber, or other locations of the user's eye. In either or bothembodiments, the ophthalmic device 100 may include alignment andseparation features that provide for radial alignment between multipleoptical elements of the ophthalmic device 100 and further provideseparation setting features that determine and set a gap of a desiredwidth between adjacent ones of the multiple optical elements.

The ophthalmic device 100 may, in general, be disc-shaped, and may havean anterior side, e.g., an external facing side, and a posterior side,e.g., an eye-ward or corneal side. The ophthalmic device 100 mayadditionally be dome shaped such that the anterior side is convex andthe posterior side is concave. In general, the ophthalmic device 100 mayhave a radius of curvature around a central axis that may be similar toa radius of curvature of at least a portion of a user's eye, such as thecornea. In some embodiments, the central axis may also be an opticalaxis of the ophthalmic device 100.

The illustrated embodiment of the ophthalmic device 100 includes aplurality of optical elements disposed in enclosure 150. In someembodiments, the plurality of optical elements may be formed into anoptical stack having, for example, a posterior optical element, a middleoptical element, and an anterior optical element. The plurality ofoptical elements and at least a portion of the enclosure 150 may beformed with the radius of curvature as discussed above. Each of theplurality of optical elements (discussed in more detail in FIGS. 2 and3) may have the alignment and separation features formed therein and/orthereon. For example, the alignment and separation features may begrooves and/or ridges that form rings around the optical elements at oneor more desired radii. For example, the one or more desired radii may be4 to 10 mm from a central axis, which may coincide with an optical axis,of the ophthalmic device 100. In general, the radial location of thealignment and separation features may be influenced by various otheraspects of the ophthalmic device 100, such as a desired area for anoptic region, etc. The alignment and separation features may form ordefine various regions in the ophthalmic device 100, such as an opticregion 102, a reservoir region 104, a dam 106, and a seal region 108.The ophthalmic device, in some embodiments, may further include anexternal region 110. The various regions may include gaps betweenadjacent optical elements that are formed by the alignment andseparation features. Additionally, the alignment and separation featuresmay assist with assembly of the ophthalmic device 100.

The enclosure 150 may be formed from a material amenable to being wornon a user's eye, or implantable into a user's eye, and may further be anoptically transmissive material (e.g., transparent, clear, etc.) thatseals the internal components and protects the eye. Enclosure 150 mayhave concave and convex surfaces similar to a contact lens, havegenerally flat surfaces, or otherwise in various embodiments. In acontact lens embodiment, enclosure 150 may be implemented as a hydrogelor other permeable polymer material that permits oxygen to reach theeye, or non-permeable materials (e.g., glass, plastic, silicon) may alsobe used. In an IOL embodiment, enclosure 150 may be implemented as asilicon enclosure, or other hermetically sealable materials. Of course,other optically transmissive and biocompatible materials may be used.

The optic region 102 may be an optically active area that providesadjustable optical power using a liquid crystal material, for example.The optic region 102 may encompass a central diameter and may include anoptical axis of the ophthalmic device 100. In some embodiments, theoptic region 102 may be around 5 mm in diameter and may be centered onthe optical axis. The liquid crystal material may be disposed in gapsformed between adjacent ones of the plurality of optical elements. Forexample, transparent or semi-transparent electrodes (not shown) of theophthalmic device 100 may be energized by one or more power sourcescontrolled by control electronics 152 to change an orientation of theliquid crystals of the liquid crystal material with respect to one ormore optical elements of the plurality of optical elements. The changein orientation of the liquid crystal material may cause a change inoptical power of the ophthalmic device 100, which may provideaccommodation to a user.

The reservoir region 104 may be radially outside of and adjacent to theoptic region 102. Alignment and separation features of each of theplurality of optical elements may be arranged to form the reservoirregion 104. The reservoir region 104 may be formed by gaps betweenadjacent ones of the optical elements, which may be smaller than, equalto, or greater than the gaps associated with the optic region 102. Thereservoir region 104 may hold excess liquid crystal material outside ofthe optic region 102, which may be included in the ophthalmic device 100during assembly, for example.

The dam 106 may prevent liquid crystal from escaping out of thereservoir region 104, and may prevent sealant material disposed in theseal region from breaching the reservoir region in a radially inwarddirection. The dam 106 may also determine gap widths between the opticalelements in the optic region 102 and the reservoir region 104. The dam106 may be formed by interlocking the alignment and separation featuresof the optical elements. For example, a sidewall, e.g., flat area, of aridge formed in one optical element may contact, e.g., rest upon, asidewall of a groove formed in an opposing optical element.Alternatively or additionally, the dam 106 may be formed by matingcurves of similar or different radii of curvature, or mating, e.g.,nesting, v-shaped features. In some embodiments, the alignment andseparation features formed on each optical element may be slightlyoffset from associated features in the opposing elements so that the dam106 is formed.

The seal region 108 may be formed radially outward of the dam 106. Theseal region 108 may be formed by large gaps between adjacent ones of theoptical elements and that may allow a sealant to be formed therein toseal in the liquid crystal material. Example sealants may include agasket or a curable adhesive, to name a couple. The seal region 108 maybe formed, for example, due to the alignment and separation features andfurther due to a thickness of the optical elements reducing in the sealregion 108.

In some embodiments, the external region 110 may be radially outside ofthe seal region 108. The external region 110 may include edges of theoptical elements, control circuitry substrates, such as controlelectronics 152, and where an anterior portion and a posterior portionof the enclosure 150 intersect and seal. In some embodiments, one ormore substrates for supporting electrical components and connections toconductors may be included in the external region 110. For example, adisc-shaped substrate may be included outside of the seal region 108that supports the control electronics 152 and connections.

The various regions of the ophthalmic device 100 may, in general,include gaps between adjacent ones of the plurality of optical elementsthat are formed by the associated alignment and separation features ofthe optical elements. The alignment and separation features, to bediscussed in more detail below, may assist with setting widths of thegaps and that further assist with radial alignment of the opticalelements to obtain concentricity between the optical elements.

FIG. 2 is a cross-sectional view of an optical stack 246 includingalignment and separation features in accordance with an embodiment ofthe present disclosure. The optical stack 246 may be an example of anoptical stack included in the ophthalmic device 100. The illustratedembodiment of the optical stack 246 includes optical elements 212, 214,and 216 having alignment and separation features 242 formed in or onsurfaces thereof. The alignment and separation features 242 may definean optic region 202, a reservoir region 204, a dam 206, and a sealregion 208 of the optical stack 246. The various regions may relate tooperational related aspects and/or assembly related aspects of theophthalmic device 200.

In general, the combination of the optical elements 212-216 may form alens that may either be worn on a user's eye or implanted into a user'seye. At least one of the optical elements 212-216 in conjunction with aliquid crystal material included in gaps between the optical elements212-216 may provide a dynamic optic capable of providing accommodationto the user.

The optical stack 246 may be formed from the optical elements 212-216.Optical elements 212 and 216 may be on opposing sides of optical element214, such that optical element 214 is sandwiched between opticalelements 212 and 216. In some embodiments, optical element 212 may be onan anterior side of the ophthalmic device 200, while the optical element216 may be on a posterior side. In such an embodiment, the opticalelement 212 may be external facing, whereas the optical element 216 maybe eye-ward or corneal facing. While these designations may be adoptedfor use in discussion of the present disclosure, they are by no meanslimiting, and the opposite designations may be adopted instead. Theoptical stack 246 may be encased in an enclosure 150. In general, theoptical stack 246 may provide the optically active elements of theophthalmic device, at least within an optic region 202.

Optical element 212 may be a planar substrate formed into disc. In someembodiments, the planar substrate may be dome-shaped such that a convexside is posterior facing and a concave side faces the optical element214. Optical element 212 may include one or more features around thedisc-shaped planar substrate, which may be formed on the anterior sideof the optical element 212. The one or more features may be disposed ata desired radius from a central axis of the optical element 212, and insome embodiments, the one or more features may extend from a firstradius to a second radius. These features, such as the groove 226 andthe ridge 228, may be physical features cut or molded into the materialof the optical element 212. The groove 226 and the ridge 228 may be partof the alignment and separation features 242 that are associated withthe optical element 212. While only a single groove and a single ridgeare shown, the alignment and separation features may include multiplegrooves and ridges. Optical element 212 may be formed from a polymer,and may be a rigid, gas permeable polymer in some embodiments. Theoptical element 212 may or may not have optical power, such as a staticoptical power.

Optical element 214 may be a planar substrate also formed into a disc.Similar to optical element 212, optical element 214 may be dome-shapedwith a convex side facing optical element 212 and a concave side facingoptical element 216. In the optic region 202, the optical element 214may have a diffraction lens structure formed on one or both sides,which, in combination with liquid crystal material 244, may provide adynamic optic. Additionally, optical element 214 may include one or morephysical features at a desired radius, which may at least partiallyalign with the radius the physical features of optical element 212 arelocated. In some embodiments, the one or more physical features may beformed on both surfaces of the planar substrate, e.g., a posteriorsurface and an anterior surface. For example, the one or more physicalfeatures may include a ride 230 and a groove 232 formed on a posteriorside, and a groove 234 and a ridge 236 formed on an anterior side of theoptical element 214. The grooves 232, 234 and ridges 230, 236 maycombined form alignment and separation features 242 associated with theoptical element 214. In some embodiments, the apex of the ridge 230 andthe base of the groove 234 may align. The groove 232 and the ridge 236may similarly align. These features of the optical element 214 mayappear as a zig zag when viewed from the side, as shown in FIG. 2. Thegrooves and ridges 232, 234 and ridges 230, 236 may combined to formkinks or buckles in the optical element 214 that when viewed from abovemay appear as topographical rings around the optical element 214, whichmay be disposed at one or more desired radii from a central axis of theoptical element 214. While optical element 214 is shown to include tworidges and two grooves, e.g. a posterior kink and an anterior kink,there may be multiple kinks in the optical element 214 to formassociated alignment and separation features 242. Similar to the opticalelement 212, the grooves 232, 234 and ridges 230, 236 may be cut into ormolded into a polymer material, such as a rigid, gas permeable polymer,used to form the optical element 214.

Optical element 216 may be a planar substrate formed into disc similarto the optical element 212. In some embodiments, the planar substratemay be dome-shaped such that a convex side faces optical element 214 anda concave side is eye-ward facing. Optical element 216 may include oneor more features disposed at a desired radius of the disc-shaped planarsubstrate, which may be formed on the posterior side of the opticalelement 216. In some embodiments, the desired radius may at leastpartially align with the radius the one or more features of the opticalelement 214 on the posterior side are disposed. These features, such asthe ridge 238 and the groove 240, may be physical features cut or moldedinto the material forming the optical element 216. The groove 240 andthe ridge 238 may be part of the alignment and separation features 242that are associated with the optical element 216. While only a single asingle instance of the alignment and separation features is shown,multiple instances of the alignment and separation features may beincluded in the optical stack 246. Optical element 216 may be formedfrom a polymer, and may be a rigid, gas permeable polymer in someembodiments. The optical element 216 may or may not have optical power,such as a static optical power.

Gaps between the optical elements 212-216 may be filled with the liquidcrystal material 244 in at least the optic region 202 and the reservoirregion 204. For example, gaps 218, 220, 222 and 224 may be filled withthe liquid crystal material 244. The liquid crystal material may, incombination with at least the optical element 314, provide a dynamicoptic to the ophthalmic device 200 by changing an orientation of theliquid crystals within the liquid crystal material 244.

The optic region 202 may be an optically active region of the ophthalmicdevice 200 and may include liquid crystal material 244 disposed betweenthe optical elements 212-216 within gaps 218 and 220. The gap 218 beinga space between optical elements 212 and 214 that may be filled with theliquid crystal material 244, and the gap 220 being a space betweenoptical elements 214 and 216 that may also be filled with the liquidcrystal material. The optic region 202 may be circular shaped and may becentered on an optical axis of the optical stack 246. The optic region202, in some embodiments, may provide a dynamic optic to a user thatprovides accommodation by changing an orientation of the liquid crystalmaterial, for example.

The reservoir region 204 may be a region that holds excess liquidcrystal material. The reservoir region 204 may be formed by the gapsbetween adjacent ones of the optical elements 212-216 that are radiallyoutside of the optic region 202. For example, the reservoir region 204may be formed by the portion of the gap 222 that is between the opticregion 202 and the dam 206. The portion of the gap 224 that is similarlysituated would also form a part of the reservoir region 204. In general,the reservoir region 204 may begin on or before the separation andalignment features 242 are located, and the change between the opticregion 202 and the reservoir region 204 may be gradual. In general, thereservoir region 204 may be radially outside of and may encircle theoptic region 202. As such, the reservoir region 204 may beannular-shaped and disposed on a perimeter of the optical stack 246.

The dam 206 may be an area where the optical elements 212-216 contact orinterlock, and may be formed to prevent the liquid crystal material 244from leaking out of the reservoir region 204 and ultimately the opticregion 202. The dam 206 may be formed by flat surfaces, e.g., sidewalls,of some of the grooves and ridges that form the alignment and separationfeatures 242. The dam 206 may be arranged radially outward from and mayencircle the reservoir region 204. In general, the dam 208 may becircumferential around a perimeter of the optical stack 246.

The seal region 208 may be a region for including a sealant, forexample, to seal in the liquid crystal material 244. The seal region 208may be formed by gaps between adjacent ones of the optical elements212-216, such as gaps 226 and 228. In some embodiments, the seal region208 may extend to an edge of the optical elements 212-216. The sealregion 208 may also be annular-shaped and encircle the dam 206.

The alignment and separation features 242 associated with each opticalelement may, when the optical elements are formed into the optical stack246, assist with radial alignment of the optical elements 212-216, andmay cause the gaps 218-228 to be formed. The alignment and separationfeatures 242 may additionally define the optic region 202, reservoirregion 204, dam 206, and seal region 208. More specifically, therelative lateral positioning and size of the alignment and separationfeatures 242 associated with each of the optical elements 212-216 mayassist with setting widths of the various gaps and assist with radialalignment of the optical elements 212-216 to obtain concentricity.

The structures that form the alignment and separation features 242 maybe formed in or on the optical elements 212-216, and may include variousangles in relation to at least one surface of the optical elements212-216. For example, the ridge 320 may extend up at an angle from ananterior surface of the optical element 214. In some embodiments, theangle may be less than 50°. In some embodiments, the angle the ridgesand grooves make with posterior and/or anterior surfaces of the opticalelements may affect various other features of the optical stack 246,such as electrical coatings formed on such surfaces for example.

The dam 206 may be formed upon stacking of the optical elements 212-216.The dam 206 may be formed in areas of the separation and alignmentfeatures 242 make contact. For example, the dam 206 may be formed whereflat sidewalls of the ridges 228 and 236 rest of flat sidewalls ofcorresponding grooves 232 and 240. The resting of the optical elements212-216 at those locations may provide intimate contact between adjacentones of the optical elements 212-216. Additionally, the ridges andgrooves that form the dam 208 may be offset from one another so that theridges and grooves do not completely nest into one another. The amountof offset in combination with the heights/depths of the ridges andgrooves may determine the widths of the various gaps 218-228. Forexample, the contact between optical elements 212 and 214 that occursbetween ridge 228 and groove 232 may determine the width of gaps 218,222, and 226. The contact point between ridge 228 and groove 232 may beaffected by their relative amount of offset and their relativeheight/depth. For example, the ridges and grooves of the opticalelements 212-216 may be around 30 to 90 microns in height/depth. Itshould also be noted that the width of gap 226, which may be larger thangaps 218 and 222, may also be formed by a change in thickness of theoptical elements 212-216 in the seal region 208.

The widths of the gaps 218 and 220 in the optic region 202 may bedetermined by the dam 208, and may also be affected by the diffractionlens formed on the optical element 214. For example, the width of gaps218 and 220 may be from 6 to 14 microns when including the diffractionlens aspect. If the diffraction lens aspect is ignored, the width ofgaps 218 and 220 may be 2 to 10 microns. The widths of gaps 222 and 224that form the reservoir region 204 may, for example, be 4 to 20 microns,and the width of gaps 226 and 228 that form the seal region 208 may befrom 20 to 100 microns. In some embodiments, the width of gaps 222 and224 may be, for example, 8 to 12 microns.

Radial alignment of the optical elements 212-216 may be assisted by thenesting of the grooves and ridges in the reservoir region 204, andfurther assisted by the width of the gap in the reservoir region 204.The grooves 226 and 232 and the ridges 230 and 238 may provide guidesfor aligning the optical axis of the optical elements 212-216, which maybe nested as shown to provide coarse alignment. Additionally, the gapwidths of the reservoir area may induce capillary forces to wick inexcess liquid crystal material 244 from the optic region 202, forexample. The capillary forces may further cause the gap widths on bothsides of the nested grooves/ridges to equilibrate, which may providemore fine radial alignment of the optical elements 212-216.

The seal region 208 may have gap widths that provide space for inclusionof sealant material 248, such as a gasket or adhesive. For example, aliquid sealant material may wick into the gaps 226 and 228. In someembodiments, the liquid sealant material may be a curable adhesive thatmay be flash cured after wicking.

The optical stack 246 may be formed through various assembly steps. Forexample, a controlled volume of liquid crystal material 244 may bedispensed in the anterior side of the optical element 212, followed bythe placement of the optical element 214 onto the volume of the liquidcrystal material 244. The alignment and separations features 242 of theoptical elements 212 and 214 may form the gap 218 and 222, and furtherradially align the two optical elements. Liquid crystal material 244that may be in excess of a volume of the optic region 202 may be pulledinto the reservoir region due to capillary forces. The capillary forcesmay cause the liquid crystal material 244 to equilibrate around thefeatures in the reservoir region 204, which may provide finer alignmentbetween the optical elements. A sealant material 248 may then be wickedinto the seal region 208 between the optical elements 212 and 214. Thesealant material 248 may then be treated to cause it to remain withinthe seal region 208.

The above steps may be performed again to add the optical element 216 tothe optical stack 246. Alternatively, the three optical elements 212-216may be assembled with the liquid crystal material 244 before sealantmaterial 248 is applied and treated.

FIG. 3 is an illustrative cross-sectional view of a portion of anophthalmic device 300 including alignment and separation features inaccordance with an embodiment of the present disclosure. The ophthalmicdevice 300 may be an example of the ophthalmic device 100. Theophthalmic device 300 may include same or similar features as theophthalmic device 200, for example, which may not be fully discussed indetail for sake of brevity. The illustrated embodiment of the ophthalmicdevice 300 includes optical elements 312, 314, and 316 that haveseparation and alignment features 342 formed therein and/or thereon. Theseparation and alignment features 342 may define an optic region 302, areservoir region 304, a dam 306, and a seal region 308. The ophthalmicdevice 300 may be worn on an eye or implanted into an eye to provideaccommodation, for example.

The optical elements 312-316 may form an optical stack, such as theoptical stack 246, and which may be encased in enclosure 350. Enclosure350 may provide a protective enclosure to the optical elements 312-316,including various other components of the ophthalmic device 300.Additionally, the enclosure 350 may be formed from a biocompatiblematerial amenable to be worn on an eye or implanted into an eye. Forexample, encasement 350 may be fabricated of a common material (e.g.,PolyMethylMethAcrylate or PMMA) or other optically transmissivematerials.

Additionally, enclosure 350 may have a size and shape that mounts overthe cornea of an eye. In the illustrated embodiment, enclosure 350includes an external side, e.g., posterior side, having a convex shapeand an eye-ward side, e.g., anterior side, having a concave shape. Ofcourse, ophthalmic device 300 may assume other shapes and geometriesincluding a piggyback configuration that attaches to a surface of aneye-mountable carrier substrate having an overall shape that resembles aconventional contact lens.

Optical element 312 may be hemispherical-shaped and may provide a topsubstrate of the optical stack. Further, the optical element 312 may bedisposed between optical element 314 and enclosure 350. The opticalelement 312 may include a groove and a ridge to form associatedalignment and separation features. For example, a shallow u-shapedgroove may extend into the optical element 312 and a v-shaped ridge mayextend out of the optical element 312. The optical element 312 may beformed from optically transmissive material, such as a transparentpolymer. In some embodiments, the optical element 312 may be formed froma rigid, gas permeable polymer. Additionally, optical element 312 mayprovide optical power to the ophthalmic device 300 in some embodiments,and, in other embodiments, may not provide any optical power.

Optical element 314 may also be hemispherical-shaped and may include adiffraction lens on one or two surfaces within an optic region 302. Forexample, a diffraction lens may be formed on an external facing side (inthe +Y direction) and/or on an eye-ward side (in the −Y direction). Theoptical element 314 may include grooves and ridges on both sides, suchas the external facing side and the eye-ward side, that form associatedalignment and separation features 342. For example, the optical element314 has an upward bend followed by a downward bend that together form aserpentine-like shape in the optical element 314. The serpentine-likeshape may form the alignment and separation features associated with theoptical element 314. The serpentine-like shape in the optical element314 may form grooves and ridges on both sides of the optical element314. The optical element 314 may be formed from similar materials as theoptical element 312 is formed.

Optical element 316 may also be hemispherical-shaped and may provide abottom substrate of the optical stack. Further, the optical element 316may be disposed between optical element 314 and enclosure 350 on theeye-ward side of the ophthalmic device 300. The optical element 316 mayinclude a groove and a ridge to form associated alignment and separationfeatures 342. For example, a shallow v-shaped ridge may extend up fromthe optical element 316, which is adjacent to a v-shaped ridge that alsoextends out of the optical element 316. In between the two v-shapedridges a groove may be formed. The optical element 316 may be formedfrom similar materials as the other two optical elements are formed.Additionally, optical element 312 may provide optical power to theophthalmic device 300 in some embodiments, and, in other embodiments,may not provide any optical power.

The separation and alignment features 342 include the ridges and groovesformed on or in each of the three optical elements. The relativelocation and interaction between the separation and alignment features342 of each of the three optical elements may result in the formation ofthe various regions of the ophthalmic device 300, such as the opticregion 302, reservoir region 304, dam 306, and seal region 308. Forexample, the flat areas of the grooves and ridges that make contact toform the dam 306 may also determine gap widths of the optic region 302and the reservoir region 304. While a gap width of the seal region 308may be additionally influenced by the dam 306, one or more of theoptical elements 312-316 may become thinner in the seal region 308,which may also determine the gap width of the seal region 308.

The optic region 302 may be the optically active area of the ophthalmicdevice 300 and may be located over the cornea of a user's eye. The opticregion 302 may include gaps between the optical elements that are filledwith a liquid crystal material, for example. The liquid crystal materialmay be electrically stimulated to change orientations so that a changein optical power is provided by the ophthalmic device 300. The gaps mayhave a width of 2 to 10 microns, which may be determined by thealignment and separation features 342 of the optical elements 312-316that form the dam 306.

The reservoir region 304 may be formed from the gaps between theadjacent optical elements that are between the optic region 302 and thedam 306. The gaps between the optical elements in the reservoir region304 may have widths that are similar to, larger than, or smaller thanthe gap widths between the optical elements in the optic region 302. Forexample, the gap widths in the reservoir region 304 may be 4 to 20microns.

The features of the optical elements that occur in the reservoir region304 provide radial alignment between the optical elements so thatconcentricity of optical axes of the optical elements may be achieved.Nesting of the grooves and ridges that occur in the reservoir region mayprovide the radial alignment. Additionally, the gap widths in thereservoir region 304 may be on an order that capillary forces areinduced in the reservoir region by the interaction of the opticalelements and the liquid crystal material. The capillary forces may causethe gap width on both sides of the nested grooves/ridges may equilibratethat may cause concentricity to be achieved. Additionally, the capillaryforces may assist with assembly of the ophthalmic device 100 by causingthe optical elements to self-align.

The features of the optical elements that form the dam 306 may belaterally offset from mirror-like features on the adjacent opticalelements. Offsetting the ridges/grooves that form the dam 306 may causea flat surface, e.g., sidewall, of the ridges/grooves to contact oneanother. For example, the ridge extending down from the optical element312 may be offset from the opposing groove of the optical element 314 sothat the dam 306 is formed where sidewalls of those two featurescontact. The amount of offset and a height/depth of the ridges/groovesmay set the gap widths in at least the optic region 302 and thereservoir region 304.

The seal region 308 may be formed radially outward of the dam 306, andmay have gap widths that are larger than the gap widths of the opticregion 302 and the reservoir region 304. For example, the gap widthsthat form the seal region 308 may be 30 to 100 microns. While the gapwidths of the seal region 308 may be larger than the other discussed gapwidths, the gap widths of the seal region may be small enough to inducewicking of a liquid sealant material into the seal region 308.

The various regions and the associated gaps may assist in the relativepositioning of the optical elements 312-316 during assembly of theoptical stack. For example, alignment and separation features 342 mayassist with radial alignment of the optical elements 312-316 to obtainconcentricity, and the dam 306 and the seal region 308 may reduce oreliminate the leakage of liquid crystal material out of the optic andreservoir regions 302, 304, respectively.

FIG. 4 is a functional block diagram of an ophthalmic device 400including alignment and separation features in accordance with anembodiment of the present disclosure. Ophthalmic device 400 may be anon-eye device, such as a contact lens or a smart contact lens, or animplantable device, such as an intraocular lens. In the depictedembodiment, ophthalmic device 400 includes an enclosure material 410formed to be either contact-mounted to a corneal surface of an eye orimplanted into an eye. A substrate 415 is embedded within or surroundedby enclosure material 410 to provide a mounting surface for a powersupply 420, a controller 425, an antenna 440, and various interconnects445 and 450. The substrate 415 and the associated electronics may be oneimplementation of the control electronics 152. The illustratedembodiment of power supply 420 includes an energy harvesting antenna455, charging circuitry 460, and a battery 465. The illustratedembodiment of controller 425 includes control logic 470, accommodationlogic 475, and communication logic 480. As shown, accommodation actuator430 is disposed in the enclosure material 410.

Power supply 420 supplies operating voltages to the controller 425and/or the accommodation actuator 430. Antenna 440 is operated by thecontroller 425 to communicate information to and/or from ophthalmicdevice 400. In the illustrated embodiment, antenna 440, controller 425,and power supply 420 are disposed on/in substrate 415, whileaccommodation actuator 430 is disposed in enclosure material 410 (notin/on substrate 415). However, in other embodiments, the various piecesof circuitry and devices contained in ophthalmic device 400 may bedisposed in/on substrate 415 or in enclosure material 410, depending onthe specific design of ophthalmic device 400. For example, in oneembodiment, accommodation actuator 430 may be disposed on a transparentsubstrate.

Substrate 415 includes one or more surfaces suitable for mountingcontroller 425, power supply 420, and antenna 440. Substrate 415 can beemployed both as a mounting platform for chip-based circuitry (e.g., byflip-chip mounting) and/or as a platform for patterning conductivematerials (e.g., gold, platinum, palladium, titanium, copper, aluminum,silver, metals, other conductive materials, combinations of these, etc.)to create electrodes, interconnects, antennae, etc. In some embodiments,substantially transparent conductive materials (e.g., indium tin oxideor silver nanowire mesh) can be patterned on substrate 415 to formcircuitry, electrodes, etc. For example, antenna 440 can be formed bydepositing a pattern of gold or another conductive material on substrate415. Similarly, interconnects 445 and 450 can be formed by depositingsuitable patterns of conductive materials on substrate 415. Acombination of resists, masks, and deposition techniques can be employedto pattern materials on substrate 415. Substrate 415 can be a relativelyrigid material, such as polyethylene terephthalate (“PET”) or anothermaterial sufficient to structurally support the circuitry and/orelectronics within enclosure material 410. Ophthalmic device 400 canalternatively be arranged with a group of unconnected substrates ratherthan a single substrate 415. For example, controller 425 and powersupply 420 can be mounted to one substrate 415, while antenna 440 ismounted to another substrate 415 and the two can be electricallyconnected via interconnects. Substrate 415 may also be a continuouspiece of semiconductor, housing all or some of the aforementioned piecesof device architecture as integrated circuitry.

Substrate 415 can be shaped as a flattened ring with a radial widthdimension sufficient to provide a mounting platform for the embeddedelectronic components. Substrate 415 can have a thickness sufficientlysmall to allow substrate f15 to be embedded in enclosure material f10without adversely influencing the profile of ophthalmic device 400.Substrate 415 can have a thickness sufficiently large to providestructural stability suitable for supporting the electronics mountedthereon. For example, substrate 415 can be shaped as a ring with adiameter of about 10 millimeters, a radial width of about 1 millimeter(e.g., an outer radius 1 millimeter larger than an inner radius), and athickness of about 50 micrometers. Substrate 415 can optionally bealigned with the curvature of the eye-mounting surface of ophthalmicdevice 400 (e.g., convex surface). For example, substrate 415 can beshaped along the surface of an imaginary cone between two circularsegments that define an inner radius and an outer radius. In such anexample, the surface of substrate 415 along the surface of the imaginarycone defines an inclined surface that is approximately aligned with thecurvature of the eye mounting surface at that radius.

In the illustrated embodiment, power supply 420 includes a battery 465to power the various embedded electronics, including controller 425.Battery 465 may be inductively charged by charging circuitry 460 andenergy harvesting antenna 455. In one embodiment, antenna 440 and energyharvesting antenna 455 are independent antennae, which serve theirrespective functions of energy harvesting and communications. In anotherembodiment, energy harvesting antenna 455 and antenna 440 are the samephysical antenna that are time shared for their respective functions ofinductive charging and wireless communications with reader 405.Additionally or alternatively, power supply 420 may include a solar cell(“photovoltaic cell”) to capture energy from incoming ultraviolet,visible, and/or infrared radiation. Furthermore, an inertial powerscavenging system can be included to capture energy from ambientvibrations.

Charging circuitry 460 may include a rectifier/regulator to conditionthe captured energy for charging battery 465 or directly powercontroller 425 without battery 465. Charging circuitry 460 may alsoinclude one or more energy storage devices to mitigate high frequencyvariations in energy harvesting antenna 455. For example, one or moreenergy storage devices (e.g., a capacitor, an inductor, etc.) can beconnected to function as a low-pass filter.

Controller 425 contains logic to choreograph the operation of the otherembedded components. Control logic 470 controls the general operation ofophthalmic device 400, including providing a logical user interface,power control functionality, etc. Accommodation logic 475 includes logicfor receiving signals from sensors monitoring the orientation of theeye, determining the current gaze direction or focal distance of theuser, and manipulating accommodation actuator 430 (focal distance of thecontact lens) in response to these physical cues. The auto-accommodationcan be implemented in real-time based upon feedback from gaze tracking,or permit the user to select specific accommodation regimes (e.g.,near-field accommodation for reading, far-field accommodation forregular activities, etc.). Communication logic 480 providescommunication protocols for wireless communication with reader 405 viaantenna 440. In one embodiment, communication logic 480 providesbackscatter communication via antenna 440 when in the presence of anelectromagnetic field 471 output from reader 405. In one embodiment,communication logic 480 operates as a smart wireless radio-frequencyidentification (“RFID”) tag that modulates the impedance of antenna 440for backscatter wireless communications. The various logic modules ofcontroller 425 may be implemented in software/firmware executed on ageneral purpose microprocessor, in hardware (e.g., application specificintegrated circuit), or a combination of both.

Ophthalmic device 400 may include various other embedded electronics andlogic modules. For example, a light source or pixel array may beincluded to provide visible feedback to the user. An accelerometer orgyroscope may be included to provide positional, rotational, directionalor acceleration feedback information to controller 425.

The illustrated embodiment also includes reader 405 with a processor482, an antenna 484, and memory 486. Memory 486 in reader 405 includesdata storage 488 and program instructions 490. As shown reader 405 maybe disposed outside of ophthalmic device 400, but may be placed in itsproximity to charge ophthalmic device 400, send instructions toophthalmic device 400, and/or extract data from ophthalmic device 400.In one embodiment, reader 405 may resemble a conventional contact lensholder that the user places ophthalmic device 400 in at night to charge,extract data, clean the lens, etc.

External reader 405 includes an antenna 484 (or group of more than oneantennae) to send and receive wireless signals 471 to and fromophthalmic device 400. External reader 405 also includes a computingsystem with a processor 482 in communication with a memory 486. Memory486 is a non-transitory computer-readable medium that can include,without limitation, magnetic disks, optical disks, organic memory,and/or any other volatile (e.g., RAM) or non-volatile (e.g., ROM)storage system readable by the processor 182. Memory 486 can include adata storage 488 to store indications of data, such as data logs (e.g.,user logs), program settings (e.g., to adjust behavior of ophthalmicdevice 400 and/or external reader 405), etc. Memory 486 can also includeprogram instructions 490 for execution by processor 482 to cause theexternal reader 405 to perform processes specified by the instructions490. For example, program instructions 490 can cause external reader 405to provide a user interface that allows for retrieving informationcommunicated from ophthalmic device 400 or allows transmittinginformation to ophthalmic device 400 to program or otherwise selectoperational modes of ophthalmic device 400. External reader 105 can alsoinclude one or more hardware components for operating antenna 484 tosend and receive wireless signals 471 to and from ophthalmic device 400.

External reader 405 can be a smart phone, digital assistant, or otherportable computing device with wireless connectivity sufficient toprovide the wireless communication link 471. External reader 405 canalso be implemented as an antenna module that can be plugged into aportable computing device, such as in an embodiment where thecommunication link 471 operates at carrier frequencies not commonlyemployed in portable computing devices. In some instances, externalreader 405 is a special-purpose device configured to be worn relativelynear a wearer's eye to allow the wireless communication link 471 tooperate with a low power budget. For example, the external reader 405can be integrated in a piece of jewelry such as a necklace, earing, etc.or integrated in an article of clothing worn near the head, such as ahat, headband, etc.

The above description of illustrated embodiments of the invention,including what is described in the Abstract, is not intended to beexhaustive or to limit the invention to the precise forms disclosed.While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various modifications arepossible within the scope of the invention, as those skilled in therelevant art will recognize.

These modifications can be made to the invention in light of the abovedetailed description. The terms used in the following claims should notbe construed to limit the invention to the specific embodimentsdisclosed in the specification. Rather, the scope of the invention is tobe determined entirely by the following claims, which are to beconstrued in accordance with established doctrines of claiminterpretation.

What is claimed is:
 1. An ophthalmic device comprising: first, second,and third optical elements arranged in a stack, each optical element ofthe first, second, and third optical elements including alignment andseparation features, wherein the alignment and separation features ofeach optical element correspond to like features on at least one of theother optical elements, the alignment and separation features defining:an optic region encircling an optical axis of each of the opticalelements, wherein the optic region has optic region gaps formed betweenadjacent ones of the first, second, and third optical elements; and adam region encircling the optic region and including a first dam formeddue to the first and second optical elements being in contact, and asecond dam formed due to the second and third optical elements being incontact, wherein the dam region determines optic region gap widths ofthe optic region gaps, wherein the ophthalmic device comprises a contactlens adapted for mounting on a cornea of an eye or an intraocular lensadapted for mounting within the eye.
 2. The ophthalmic device of claim1, wherein the alignment and separation features further form areservoir region to provide lateral alignment to the first, second, andthird optical elements such that the optical axis of each opticalelement is aligned, the reservoir region having reservoir region gapsformed between adjacent ones of the first, second, and third opticalelements, wherein the reservoir region is disposed between the opticregion and the dam region, and wherein the dam region determinesreservoir region gap widths of the reservoir region gaps.
 3. Theophthalmic device of claim 2, wherein the optic region gap widths andthe reservoir region gap widths are different widths.
 4. The ophthalmicdevice of claim 2, wherein a liquid crystal material is disposed withinthe optic region gaps and the reservoir region gaps.
 5. The ophthalmicdevice of claim 2, wherein the reservoir region is coupled to holdexcess liquid crystal material from the optic region.
 6. The ophthalmicdevice of claim 1, wherein the alignment and separation features furtherform a seal region, disposed outward of the dam region, the seal regionhaving seal region gaps formed between adjacent ones of the first,second, and third optical elements, wherein the dam region determinesseal region gap widths of the seal region gaps.
 7. The ophthalmic deviceof claim 1, wherein the dam region prevents liquid crystal material fromescaping the reservoir area in a radially outward direction.
 8. Theophthalmic device of claim 1, wherein the alignment and separationfeatures are formed from grooves and ridges disposed on one or moresurfaces of each of the first, second, and third optical elements. 9.The ophthalmic device of claim 8, wherein the grooves and ridges of thefirst optical element are formed on one surface of the first opticalelement, the one surface of the first optical element facing the secondoptical element.
 10. The ophthalmic device of claim 8, wherein thegrooves and ridges of the third optical element are formed on onesurface of the third optical element, the one surface of the thirdoptical element facing the second optical element.
 11. The ophthalmicdevice of claim 8, wherein the grooves and ridges of the second opticalelement are formed on two surfaces of the second optical element,wherein one of the two surfaces faces the first optical element, and theother of the two surfaces faces the third optical element.
 12. Anapparatus, comprising: first, second, and third optical elementsarranged in a stack, wherein each of the first, second, and thirdoptical elements include alignment and separation features correspondingto like features on at least one of the other first, second, and thirdoptical elements, wherein the alignment and separation features providelateral alignment between the first, second, and third optical elements,wherein adjacent ones of the first, second, and third optical elementsare coupled at sidewalls of the alignment and separation features toform a dam, wherein an optic region is formed by respective gaps betweenadjacent ones of the first, second, and third optical elements, whereina width of the respective gaps formed between adjacent ones of thefirst, second, and third optical elements is determined by the sidewallsof the alignment and separation features that couple to form the dam,and wherein the dam seals liquid crystal material disposed in at leastone of the respective gaps between the first, second, and third opticalelements from leaking outward away from the optic region.
 13. Theapparatus of claim 12, wherein the alignment and separation featuresincluded in each of the first, second, and third optical elements areannular-shaped, and wherein the alignment and separation features definethe optic region, a reservoir region, and a seal region.
 14. Theapparatus of claim 13, wherein the dam formed between the first andsecond optical elements determines widths of optic region gaps,reservoir region gaps, and seal region gaps formed between the first,second, and third optical elements.
 15. The apparatus of claim 13,wherein the seal region formed between adjacent ones of the first,second, and third optical elements is formed for inclusion of a sealantmaterial.
 16. The apparatus of claim 15, wherein the dam prevents thesealant material from breaching the reservoir region in an inwarddirection.
 17. The apparatus of claim 13, wherein the liquid crystalmaterial is disposed within the respective gaps forming the optic regionand the reservoir region.
 18. The apparatus of claim 12, wherein thealignment and separation features included in each of the first, second,and third optical elements include one or more ridges and one or moregrooves arranged to at least partially align to mirror-like grooves andridges on an adjacent one of the first, second, and third opticalelements.
 19. The apparatus of claim 18, wherein a ridge of the secondoptical element nests within a groove of the first optical element toprovide lateral alignment between the first and second optical elements,and wherein a sidewall of a ridge of the first optical element rests ona sidewall of a groove of the second optical element to form the dambetween the first and second optical elements.
 20. The apparatus ofclaim 18, wherein a ridge of the third optical element nests within agroove of the second optical element to provide the lateral alignmentbetween the second and third optical elements, and wherein a sidewall ofa ridge of the second optical element rests on a sidewall of a groove ofthe third optical element to form the dam between the second and thirdoptical elements.
 21. An ophthalmic device comprising: first, second,and third optical elements arranged in a stack, each optical element ofthe first, second, and third optical elements including alignment andseparation features, wherein the alignment and separation features ofeach optical element correspond to like features on at least one of theother optical elements, the alignment and separation features defining:an optic region encircling an optical axis of each of the opticalelements, wherein the optic region has optic region gaps formed betweenadjacent ones of the first, second, and third optical elements; and adam region encircling the optic region and including a first dam formeddue to the first and second optical elements being in contact, and asecond dam formed due to the second and third optical elements being incontact, wherein the dam region determines optic region gap widths ofthe optic region gaps, wherein the dam region dams liquid crystalmaterial disposed in at least one of the optic region gaps to impedeleakage of the liquid crystal material outward away from the opticregion.